class Net::SSH::Connection::Session

def close

connection.
successfully closed, and then closes the underlying transport layer
Closes the session gracefully, blocking until all channels have 
def close
  info { "closing remaining channels (#{channels.length} open)" }
  channels.each { |id, channel| channel.close }
  begin
    loop(0.1) { channels.any? }
  rescue Net::SSH::Disconnect
    raise unless channels.empty?
  end
  transport.close
end